By NICHOLAS RAJKOVICH

Assistant professor of architecture

Reprinted from The Conversation

In May of this year, a hot spell broiled Boston. In June,
extreme temperatures grounded Phoenix’s planes. Last week,
Seattle suffered under record temperatures.

When a heat wave is forecast, the standard advice is to drink
plenty of water, take frequent breaks and wear sunscreen. But for
extreme heat events, those steps may not be enough.

Over 30 percent of all weather-related deaths in the United
States are attributable to high outdoor temperatures, heat stroke
or sunstroke. And heat waves are expected to increase in intensity
with climate change.

How should U.S. cities prepare for extreme heat events? My
research shows that the answer isn’t clear-cut, and that they
should pursue multiple solutions rather than looking for one
“best” option.

How to cool off

In a 2016 article for the Michigan
Journal of Sustainability, I explored how Cuyahoga County,
Ohio, addresses high temperatures. I chose northeast Ohio because
it is one of the most vulnerable areas of the United States: The
region has an older population, poor-quality housing stock and less
central air conditioning than the national average.

Although Cleveland and its suburbs are at risk, public health
experts view healthy housing and environmental programs developed
there as national models. I also hoped that research results would
be useful to other cities in the Great Lakes region.

I focused on the perceptions of a specific set of people —
professionals from the health, building and urban sectors —
because they have significant influence on how programs and
policies are created. Professionals also tend to serve as experts,
operating in a middle area between government officials and the
public.

After attending numerous municipal meetings, reading reams of
policy documents and completing dozens of interviews, I was
surprised to find that local professionals disagreed on how to
prepare for heat waves. Public health officials felt that cooling
centers and air conditioning were critical. Energy efficiency
experts wanted to see more funding spent on home energy efficiency.
City planners called for increasing tree cover to shade pavement
and buildings.

This made me wonder: If the experts don’t agree, is there
one approach that works better than others?

Active, passive and urban cooling

Cooling centers and central air conditioning protect people by
lowering indoor air temperature and humidity. However, not everyone
can access cool locations like libraries or recreation centers
during heat waves. Some people have limited mobility or lack access
to transportation. For this reason, public health officials often
tout residential air conditioning as an important intervention.

Unfortunately, air conditioning is an “active”
system. It requires electricity and doesn’t work when the
power is out. This is a problem because as the mercury climbs,
blackouts also increase.

As a result, building energy-efficiency experts are interested
in “passive” cooling systems — solutions that
don’t depend on the electrical grid. Window shades,
light-colored building materials and radiant barriers in attics are
time-honored techniques. If the power goes out, these systems can
still help. This is called improving “passive
survivability.”

But while these techniques moderate interior temperatures,
indoor conditions are still typically within a few degrees of the
outdoor air temperature. This means that if it’s over 100
degrees Fahrenheit (38 degrees Celsius) in the afternoon,
it’s still going to be in the 90°F (32°C) range
indoors. Passive systems alone won’t help vulnerable
populations like the elderly ride out extreme heat events.

This is why city planners advocate for planting street trees to
promote urban cooling. Leafy trees and shrubs provide shade and
increase evaporation of water from the ground, cooling the air. But
like passive systems, these approaches serve only to moderate local
temperatures. If a massive heat wave settles over a region,
it’s still going to be extremely hot outside.

Since no approach is foolproof, why not apply all of these
strategies? One challenge is that with limited funding, there may
not be enough money to go around.

Moreover, these strategies may actually conflict with one
another. Air conditioning systems reduce interior temperatures, but
they increase household energy consumption, undoing the work of
energy-efficiency experts. In addition, air conditioners exhaust
waste heat from inside houses to the outdoors, further warming
surrounding neighborhoods.

To address these conflicts, we need to make stronger connections
between the environmental health science, building science and
urban climate communities. Fortunately, cities like Cleveland are
making strides in this direction.

Collaborative cooling

With support from the Kresge Foundation’s Climate
Resilience and Urban Opportunity Initiative, the city of Cleveland,
Cleveland Neighborhood Progress, the Cleveland Urban Design
Collaborative and UB’s Resilient Buildings Lab recently
hosted a series of neighborhood discussions to better understand
how climate change will affect Cleveland neighborhoods. One major
concern is preparing for future heat waves.

The effort, led by Cleveland Neighborhood Progress, generated a
series of climate adaptation strategies, including complementary
ideas to reduce heat stress at the house, block, neighborhood and
city levels. These ideas were incorporated into a climate resilience plan
that will guide local efforts through 2018.

Although it’s still early in the process, results from
this collaborative effort are encouraging. Community members are
engaging with city staff and preparing climate emergency kits to
distribute to residents. These kits will contain information on
cooling centers, weather radios to keep residents informed, and
guidance on stocking food and water to ride out a multi-day
emergency without power.

Scholars from university health, architecture and planning
departments are also discussing heat preparedness challenges with
the Cleveland emergency operations center and local community
development corporations. Current efforts focus on setting up
additional cooling centers, weatherizing homes and using vacant
lots as green space to buffer temperatures.

In Cleveland, preparing for extreme heat events has brought
professionals together and encouraged overlapping approaches
because no single strategy is foolproof. Other cities, like
Baltimore and Providence, are working on similar multifaceted
approaches.

No city wants to repeat what happened in Chicago in 1995, when
approximately 700 people died during a weeklong heat wave. But with
a collaborative approach to heat-wave planning, perhaps cities can
lower the risk of harm from hot weather.